首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1022篇
  免费   45篇
  国内免费   7篇
耳鼻咽喉   18篇
儿科学   54篇
妇产科学   12篇
基础医学   102篇
口腔科学   23篇
临床医学   152篇
内科学   238篇
皮肤病学   22篇
神经病学   104篇
特种医学   23篇
外科学   123篇
综合类   25篇
一般理论   1篇
预防医学   38篇
眼科学   14篇
药学   84篇
中国医学   4篇
肿瘤学   37篇
  2023年   11篇
  2022年   11篇
  2021年   49篇
  2020年   24篇
  2019年   41篇
  2018年   50篇
  2017年   27篇
  2016年   32篇
  2015年   41篇
  2014年   45篇
  2013年   62篇
  2012年   78篇
  2011年   78篇
  2010年   55篇
  2009年   33篇
  2008年   62篇
  2007年   66篇
  2006年   65篇
  2005年   43篇
  2004年   27篇
  2003年   31篇
  2002年   11篇
  2001年   4篇
  2000年   12篇
  1999年   6篇
  1996年   6篇
  1995年   2篇
  1993年   5篇
  1992年   4篇
  1991年   7篇
  1990年   5篇
  1989年   11篇
  1988年   7篇
  1987年   2篇
  1986年   5篇
  1985年   3篇
  1984年   2篇
  1983年   5篇
  1982年   2篇
  1978年   2篇
  1977年   3篇
  1976年   2篇
  1975年   4篇
  1973年   2篇
  1972年   3篇
  1971年   3篇
  1970年   7篇
  1969年   2篇
  1968年   3篇
  1967年   3篇
排序方式: 共有1074条查询结果,搜索用时 15 毫秒
61.
62.
OBJECTIVES: Transjugular intrahepatic portosystemic stent shunt (TIPSS) is now widely used in the treatment of uncontrolled and recurrent variceal haemorrhage. This study reports the outcome and long-term follow-up of 125 patients who were referred to a single centre for TIPSS. METHODS: One hundred and twenty-five patients were referred to undergo TIPSS. All but 10 had variceal haemorrhage. The 10 patients referred with refractory ascites were excluded from the analysis. Our follow-up protocol was to assess shunt patency only if bleeding recurred or there was a clinical indication. The mean age was 51.5 years (range 18-87 years) and 64 patients (56%) were male. The commonest aetiology for chronic liver disease was alcohol (80%). At referral, 19 patients (16%) were Child-Pugh class A, 26 patients (23%) were Child-Pugh class B and 70 patients (61%) were Child-Pugh class C. The mean follow-up period was 20.4 months (range 0-95 months). RESULTS: TIPSS was successfully placed in 108 of 115 patients (94%). The thirty-day mortality was 30%. One-year and 2-year overall cumulative survival was 52% (survival ratio, 0.525; 95% confidence interval, 0.432-0.619) and 43% (survival ratio, 0.436; 95% confidence interval, 0.340-0.532), respectively. CONCLUSION: TIPSS is effective in the treatment of uncontrolled or recurrent variceal bleeding. In comparison with previously published studies, our study suggests no value in regular or routine shunt surveillance to reduce rebleeding episodes or mortality, but this needs to be further assessed in prospective randomized studies.  相似文献   
63.
64.
65.
66.
Free radicals and inflammatory mediators are involved in transient focal cerebral ischemia (FCI). Preadministration of N-acetylcysteine (NAC) has been found to attenuate the cerebral ischemia-reperfusion injury in a rat model of experimental stroke. This study was undertaken to investigate the neuroprotective potential of NAC administered after ischemic events in experimental stroke. FCI was induced for 30 min by occluding the middle cerebral artery (MCA). NAC (150 mg/kg) was administered intraperitoneally at the time of reperfusion followed by another dose 6 hr later. Animals were sacrificed after 24 hr of reperfusion. The cerebral infarct consistently involved the cortex and striatum. Infarction was assessed by staining the brain sections with 2,3,5-triphenyltetrazolium chloride. Animals treated with NAC showed a significant reduction in infarct area and infarct volume and an improvement in neurologic scores and glutathione level. Reduction in infarction was significant even when a single dose of NAC was administered at 6 hr of reperfusion. Immunohistochemical and quantitative real-time PCR studies demonstrated a reduction in the expression of proinflammatory cytokines such as tumor necrosis factor alpha (TNFalpha) and interleukin 1beta (IL-1beta) and inducible nitric oxide synthase (iNOS) in NAC compared to that in vehicle-treated animals. The expression of activated macrophage/microglia (ED1) and apoptotic cell death in ischemic brain was also reduced by NAC treatment. These results indicate that in a rat model of experimental stroke, administration of NAC even after ischemia onset protected the brain from free radical injury, apoptosis, and inflammation, with a wide treatment window.  相似文献   
67.
The aim of the study was to develop four appropriate three-in-one weight, height and built in body mass index (BMI) charts, for under-fives, 0-5-year-olds, > 5-10-year-olds, > 10-18-year-olds, and adults and to delineate the normal range, underweight, overweight and obesity on the above charts. Four different charts were designed for the various age groups as indicated above. Height was made available on the x-axis, weight on the y-axis, and corresponding BMI values on the right margin. Shading of the normal range to denote the health path and marking of the cut-off curves to denote normal status, overweight, and obesity were done selecting appropriate round figures to suit both sexes in accordance with the International Obesity Task Force (IOTF) recommendations for the various age groups. Field trials were done on appropriate subjects belonging to various age groups. 500 in each group with equal male to female ratio. The field trials showed that all the studied subjects belonging to both sexes came within the purview of the chart and those with normal nutritional status, underweight, overweight, and obesity could easily be identified looking at the chart without doing any further calculation. Early intervention also could be advised as the chart could demonstrate how much weight should be gained or reduced to come within the health path. In conclusion, the charts are applicable to both sexes and are user friendly. These are appropriate for general screening of nutritional status and to determine underweight, overweight, and obesity from birth to adulthood. They give a visual display of the ideal health path with respect to weight, height, and BMI and the adjustment in weight required to reach the normal range.  相似文献   
68.
Abdominal compartment syndrome related to noninvasive ventilation   总被引:2,自引:0,他引:2  
OBJECTIVE: To study the effects of noninvasive positive pressure ventilation (NIPPV) on intra-abdominal pressure. DESIGN AND SETTING: Single case report from a tertiary teaching hospital. PATIENTS AND METHODS: A 65-year-old man who experienced a sudden respiratory and cardiovascular collapse during NIPPV. This was caused by gastric overdistension due to aerophagia followed by raised intra-abdominal pressure leading to intra-abdominal hypertension and abdominal compartment syndrome. RESULTS: The respiratory and cardiovascular problems resolved immediately after the introduction of a nasogastric tube. This resulted in normalization of IAP. CONCLUSIONS: This is the first case reported of an abdominal compartment syndrome related to NIPPV. Clinicians should be aware of this possible complication while using NIPPV.  相似文献   
69.
A prospective hospital based study was conducted in the Department of Pediatrics of the Kasturba Hospital, Mahatma Gandhi Institute of Medical Sciences, Sevagram, Wardha to predict the mortality in children admitted with fever and unconsciousness using the Modified Glasgow Coma Scale (MGCS) score. Forty eight children were admitted with fever and unconsciousness; cases of febrile convulsions, epilepsy and cerebral palsy were excluded. MGCS scores were assessed on admission and repeated at 12 hours, 24 hours, 48 hours and 72 hours after admission in each case. Diagnosis in each case was confirmed by history, examinations and investigations. All the cases were regularly followed up till death/discharge. The overall mortality was 29.1% (14/ 48) out of which 85% (12/14) died within the first 24 hours. Mortality was highest in the toddler age group and in patients with pyogenic meningitis. There was a significant association between death and MGCS scores on admission with a post test probability for discharge being only 10% with a score of less than 5 and 99% with a score of more than 10 respectively. MGCS scores on admission can be used to predict mortality in patients hospitalized with fever and unconsciousness. The scale is simple, easy, can be applied at bed side and does not need any investigations. Its application in developing countries with limited investigative and intensive care facilities can help the treating physician decide regarding referral and counseling the parents regarding the probable clinical outcome.  相似文献   
70.
Glanzmann thrombasthenia (GT) is an autosomal recessive platelet function disorder characterized by mucocutaneous bleeding as the most common clinical phenotype. Patients with GT have normal platelet counts, platelet morphology but reduced platelet aggregation in response to various agonists. Homozygosity or compound heterozygosity for variants in the ITGA2B/ITGB3 genes is the genetic basis for GT. Establishing a molecular diagnosis is definitive and is important for predictive testing. Using multi-gene panels is an accurate, faster, and cost-effective mode as compared to Sanger sequencing in large genes. We used a targeted resequencing based approach to identify pathogenic variants in eight cases in seven families. These variants were validated using Sanger sequencing in patients as well as family members and were predicted probably pathogenic using in-silico prediction tools. The variants include three missense (3/7 = 43%) (ITGA2B:c.1028 T > C, ITGA2B:c.1186G > A, ITGB3:c.1388G > C), two deletions (ITGA2B:c.559delG, ITGA2B:c.3092delT), one duplication (ITGA2B:c.1424_1427dupAGGT) and nonsense variant (ITGA2B:c.2578C > T, p.Gln860Ter). Except for one case which was compound heterozygous, the rest of the cases were homozygous. We found two novel variants that are reported for the first time in GT. The targeted resequencing based approach revealed varied genetic variants in North Indian patients, including two novels ones. The high yield of our panel indicates its suitability for usage in larger cohorts for the genetic diagnosis of GT patients. This approach is cost-effective and less cumbersome as compared to Sanger sequencing for these large size genes with multiple exons. The information so obtained is helpful in prenatal testing, carrier analysis, and genetic counseling.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号